/* Copyright (c) 2012, Knowledge Media Institute
 * All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
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 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of the <organization> nor the
 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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package uk.ac.open.kmi.fusion.api.impl.transformation;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import uk.ac.open.kmi.fusion.api.IAttribute;
import uk.ac.open.kmi.fusion.api.ITransformationFunction;
import uk.ac.open.kmi.fusion.api.impl.TransformationAttribute;

public class ConcatenateAttributesTransformationFunction implements
		ITransformationFunction<String> {

	private static ConcatenateAttributesTransformationFunction INSTANCE = new ConcatenateAttributesTransformationFunction();
	
	private ConcatenateAttributesTransformationFunction() {
		
	}
	
	public static ConcatenateAttributesTransformationFunction getInstance() {
		return INSTANCE;
	}

	@Override
	public List<String> getTransformationResult(TransformationAttribute top, Map<IAttribute, List<? extends Object>> operands) {
		StringBuffer result = new StringBuffer();
		
		List<String> res = new ArrayList<String>(1);
		
		List<IAttribute> attributes = top.getAttributes();
		
		List<? extends Object> operandList;
		for(IAttribute attr : attributes) {
			operandList = operands.get(attr);
			if(operandList!=null) {
				for(Object operand : operandList) {
					if(operand!=null) {
						result.append((operand.toString()));
						result.append(" ");
					}
				}
			}
		}
		res.add(result.toString());
		return res;
	}

	@Override
	public boolean isSuitableForAttributes(List<IAttribute> attributes) {
		return true;
	}

	
	
}
